It has taken ten years to get this long-in-development project before the cameras, but the wait, bound to surprise many, has been well worth it. Directed with visual energy and narrative know-how by Ronny Yu (1998's "Bride of Chucky"), "Freddy Vs. Jason" is as unexpectedly entertaining and well-made as any other film this summer. Pitting the horribly burned, razor-clawed dream stalker Freddy Krueger (Robert Englund) against the unstoppable, hockey-masked psychopath Jason Voorhees (Ken Kirzinger) may sound like a trashily novel idea, but it could have easily turned into a laughable, cheesy disaster. Worse yet, it could have been snore-inducing (see 2002's "Jason X"). What no one may be prepared for, then, is just how inventive and expertly designed the finished project is.

Having been long-since forgotten by the new children of his old stomping ground, Elm Street, Freddy Krueger's power over his potential victims' dreams has been rendered impotent. Having laid dormant for far too long, he enlists the aid of deceased psychopath Jason Voorhees to rise from the dead and reinject fear into Elm Street. By doing this, Freddy hopes to regain his own reputation and, thus, his power to kill teenagers in their dreams. Unfortunately, when Jason carries out his murderous job with more aplomb than expected, Freddy quickly grows fed up with Jason hogging the spotlight, and vows to stop Jason himself. Caught in the middle of Freddy and Jason's escalating war are several unlucky victims-to-be, who turn out to be more intelligent and savvy than the teenage norm in slasher flicks. They include the virginal Lori (Monica Keena), old boyfriend Will (Jason Ritter), the look-obsessed Kia (Kelly Rowland), and troubled wild girl Gibb (Katharine Isabelle).

The makers of "Freddy Vs. Jason," including director Ronny Yu and first-time screenwriters Damian Shannon and Mark Swift, give long-time fans of both the "Friday the 13th" and "Nightmare on Elm Street" series' exactly what they have been waiting for, and then go one step further. The plot is cleverly constructed and imaginative, successfully interweaving plot threads from both sagas; the lead core of teen characters are more realistic and developed than usual, especially by the standards of the low-grade, one-note "Friday the 13th" pictures; and the pace never lags for a second.

Best of all, Freddy Kruegerwho started as a truly frightening figure before being turned into a stand-up comedian in later installmentsis as threatening as he has been since 1984's original "A Nightmare on Elm Street." While he does still drop a few one-liners, they are actually worth laughing about rather than eyeroll-inducing. Meanwhile, the past of Jason Voorhees, which has rarely gone much beyond the fact that he is a silent stalker with a machete, is explored more in-depth than ever before, making him into a more palpable and troubled villain. Following a nine-year hiatus, Robert Englund slips back into the showy part of Freddy Krueger like a well-worn glove, only with an even nastier undercurrent. It helps that his burn make-up and costume design, including new demonic contact lenses, are first-rate. Taking over for Jason regular Kane Hodder, Ken Kirzinger makes Jason his own while never straying far from how the titular villain usually acts.

Director Ronny Yu delights in playing with the mythology of both characters, while at the same time taking advantage of a film that includes a real-life killer and one that lurks in people's dreams. In one particularly ingenious and horrific sequence, a character passes out at a rave after having too much to drink. Just as she is about to be killed by Freddy in her dream, she is impaled along with her unbeknownst date rapist by Jason. Moralistic and more sexually charged than the norm, the film also has the auspiciousness to explore Freddy's own sexual hang-ups, implying that his razor-knifed gloves are compensation for a small penis.

As the in-danger teens, who actually use their brains while thinking of a way to pit Freddy against Jason, Monica Keena (2002's "Orange County") and Katharine Isabelle (2002's "Insomnia") stand out the most. As the distressed Lori, Keena refreshingly plays the grim realities of the situation she is in rather than the usual movie-style version of coping with the loss of her friends. As such, she cries for much of the film as she grieves (instead of just forgetting her dead friends seconds after they bite the dust), even as she finds the strength inside of her to defeat both monsters. As Gibb, the very talented Isabelle refuses to be just another tree stump on Jason and Freddy's chopping block, injecting real emotion and truth into her every moment. In lesser hands, this supporting part would be nothing special, but Isabelle turns Gibb into someone the viewer can identify with. Additionally, Destiny's Child singer Kelly Rowland brings real spunk to her role of Kia; all things considered, she actually outperforms fellow band member Beyonce Knowles' debut role in 2002's "Austin Powers in Goldmember."

With atmospheric cinematography by Fred Murphy (2002's "The Mothman Prophecies"), who often stylishly paints his images with indelible red and green filters, "Freddy Vs. Jason" is a B-movie that looks more like an A-list picture. When the battle between Freddy and Jason finally gets off and running in the last half-hour (taking place first in Jason's boiler room nightmare, and then in the real world at Camp Crystal Lake), it is a thrilling, crowd-pleasing tour de force that comes up with a smart, unpredictable way to please both those rooting for Jason, and those for Freddy.

Believe it or not, "Freddy Vs. Jason" is better than any of the other ten "Friday the 13th" movies, and places in the upper half of the previous seven-parted "Nightmare on Elm Street" series. Its avoidance of audience condescension, lack of pretentiousness, and return to what made horror fans hold a fondness for both series' in the first place makes "Freddy Vs. Jason" a far-better-than-expected, late summer thrill ride. It may not be very scary, but it sure is loads of fun.